Compatibility of almond varieties on Marianna 2624 plum rootstock

Vegetatively propagated Marianna 2624 plum is sometimes used as an almond rootstock, primarily because it as greater tolerance (but not immunity) to oak root fungus (Armillaria mellea) than do other stone fruit rootstocks. It is also adapted to heavy, wet soil conditions. The varieties, Texas (Mission), Peerless, the Plus Ultra, Jordanolo and, in most cases, IXL make satisfactory orchard trees on this stock. Tree size is somewhat reduced however, with considerable over-growth occurring at the union. Nonpareil, Davey and Drake are incompatible with Marianna 2624. Additional information reported here is from tests started in 1958 a the compatibility relationships of some ewer commercial almond varieties with Marianna 2624 and the effect of an inter-stock to overcome incompatibility with the commercially desirable Nonpareil.